/*
	This file is part of the OdinMS Maple Story Server
    Copyright (C) 2008 Patrick Huy <patrick.huy@frz.cc> 
                       Matthias Butz <matze@odinms.de>
                       Jan Christian Meyer <vimes@odinms.de>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU Affero General Public License version 3
    as published by the Free Software Foundation. You may not use, modify
    or distribute this program under any other version of the
    GNU Affero General Public License.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU Affero General Public License for more details.

    You should have received a copy of the GNU Affero General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
*/

package org.snow.odinms;

import java.io.ByteArrayOutputStream;
import java.nio.ByteBuffer;
/**
 * Provides a class for manipulating hexadecimal numbers.
 * 
 * @author Frz
 * @since Revision 206
 * @version 1.0
 */
public class HexTool {
	static private char[] HEX = { '0', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'A', 'B', 'C', 'D', 'E', 'F' };

	/**
	 * Static class dummy constructor.
	 */
	private HexTool() {
	}

	/**
	 * Turns a byte into a hexadecimal string.
	 * 
	 * @param byteValue The byte to convert.
	 * @return The hexadecimal representation of <code>byteValue</code>
	 */
	public static String toString(byte byteValue) {
		int tmp = byteValue << 8;
		char[] retstr = new char[] { HEX[(tmp >> 12) & 0x0F], HEX[(tmp >> 8) & 0x0F] };
		return String.valueOf(retstr);
	}

	/**
	 * Turns a <code>org.apache.mina.common.ByteBuffer</code> into a
	 * hexadecimal string.
	 * 
	 * @param buf The <code>org.apache.mina.common.ByteBuffer</code> to
	 *            convert.
	 * @return The hexadecimal representation of <code>buf</code>
	 */
	public static String toString(ByteBuffer buf) {
		buf.flip();
		byte arr[] = new byte[buf.remaining()];
		buf.get(arr);
		String ret = toString(arr);
		buf.flip();
		buf.put(arr);
		return ret;
	}

	/**
	 * Turns an integer into a hexadecimal string.
	 * 
	 * @param intValue The integer to transform.
	 * @return The hexadecimal representation of <code>intValue</code>.
	 */
	public static String toString(int intValue) {
		return Integer.toHexString(intValue);
	}

	/**
	 * Turns an array of bytes into a hexadecimal string.
	 * 
	 * @param bytes The bytes to convert.
	 * @return The hexadecimal representation of <code>bytes</code>
	 */
	public static String toString(byte[] bytes) {
		if (bytes == null || bytes.length < 1) {
			return "";
		}
		StringBuilder hexed = new StringBuilder();
		for (int i = 0; i < bytes.length; i++) {
			hexed.append(toString(bytes[i]));
			hexed.append(' ');
		}
		return hexed.substring(0, hexed.length() - 1);
	}

	/**
	 * Turns an array of bytes into a ASCII string. Any non-printable characters
	 * are replaced by a period (<code>.</code>)
	 * 
	 * @param bytes The bytes to convert.
	 * @return The ASCII hexadecimal representation of <code>bytes</code>
	 */
	public static String toStringFromAscii(byte[] bytes) {
		char[] ret = new char[bytes.length];
		for (int x = 0; x < bytes.length; x++) {
			if (bytes[x] < 32 && bytes[x] >= 0) {
				ret[x] = '.';
			} else {
				int chr = ((short) bytes[x]) & 0xFF;
				ret[x] = (char) chr;
			}
		}
		return String.valueOf(ret);
	}
	
	public static String toPaddedStringFromAscii(byte[] bytes) {
		String str = toStringFromAscii(bytes);
		StringBuilder ret = new StringBuilder(str.length() * 3);
		for (int i = 0; i < str.length(); i++) {
			ret.append(str.charAt(i));
			ret.append("  ");
		}
		return ret.toString();
	}

	/**
	 * Turns an hexadecimal string into a byte array.
	 * 
	 * @param hex The string to convert.
	 * @return The byte array representation of <code>hex</code>
	 */
	public static byte[] getByteArrayFromHexString(String hex) {
		ByteArrayOutputStream baos = new ByteArrayOutputStream();
		int nexti = 0;
		int nextb = 0;
		boolean highoc = true;
		outer: for (;;) {
			int number = -1;
			while (number == -1) {
				if (nexti == hex.length()) {
					break outer;
				}
				char chr = hex.charAt(nexti);
				if (chr >= '0' && chr <= '9') {
					number = chr - '0';
				} else if (chr >= 'a' && chr <= 'f') {
					number = chr - 'a' + 10;
				} else if (chr >= 'A' && chr <= 'F') {
					number = chr - 'A' + 10;
				} else {
					number = -1;
				}
				nexti++;
			}
			if (highoc) {
				nextb = number << 4;
				highoc = false;
			} else {
				nextb |= number;
				highoc = true;
				baos.write(nextb);
			}
		}
		return baos.toByteArray();
	}
	
	public static String getIpStringFromBytes(byte[] bytes) {
	    if (bytes.length != 4) {
		return null;
	    }
	    String ip = "";
	    int segment = 1;
	    for(byte b : bytes) {
		ip += (b & 0xFF);
		if (segment != 4) {
		    ip += ".";
		}
		segment++;
	    }
	    return ip;
	}
	
	public static byte[] xorBytes(byte[] a, byte[] b) {
		byte[] retbytes = new byte[a.length];
		for (int i = 0; i < a.length; i++) {
			retbytes[i] = (byte) (a[i] ^ b[i]);
		}
		return retbytes;
	}
	
	public static String getOpcodeToString(short op) {
	    String ret = "0x";
	    ret += StringUtil.getLeftPaddedStr(Integer.toHexString(op).toUpperCase(), '0', 4);
	    return ret;
	}
}
